Devices are currently available for dispensing volatile materials, such as a single scent into a room and in automobiles. Examples of devices for dispensing a single scent into a room include GLADE PLUG INS® plug in room fresheners manufactured by S. C. Johnson. Devices capable of dispensing scented materials are also described in the patent literature. Examples of such devices are described in: U.S. Pat. Nos. 4,549,250; 4,714,984, 4,695,434; 4,629,604; and 5,805,768; and in PCT Publication WO 97/02076 and Canadian Patent Application 2,222,838; PCT Publication WO 00/121,143; and U.S. Patent Publications 2002/0066798, 2002/0066967, 2002/0068009, and 2002/0068010. The search for improved devices and systems, however, has continued.